Kevin Kline’s post-Academy Award career hasn’t been the most glorious. The performances were often there, but the acclaim and box office rewards, not so much.

But every so often, a piece comes along tailor made for the man, and “The Extra Man,” which didn’t earn wide release, is such a film. Kline plays something of a gigolo.

“Don’t be disgusting. I’m an extra man — essential. There’s always a need for an extra man at the table.”

A dapper, down-on-the-heels college professor who uses his erudite manners and fading good looks to ingratiate himself with the elderly members of the Manhattan/The Hamptons/Palm Beach set, Henry Harrison is determined to be a mentor to young would-be writer Louis Ives (Paul Dano, wonderfully weird).

But Young Louis, whose tale this ostensibly is (the plummy voiced narrator services Louis’ story), as new to the Big City as he is, is no unsophisticated bumpkin. He’s just lost a position with an exclusive boarding school, at least partly for his penchant for ladies’ undergarments. He fancies himself a latter day F. Scott Fitzgerald, he lies to and crushes on the cruelly cute environmentalist (Katie Holmes, good) at his new employer, an environmental magazine.

And Louis shares a flat with Henry, whose academic career is merely a front for thwarted playwriting fame.

And Henry is nothing if not theatrical. He regales Louis of his feuds, his swearing off of sex and love and the requisite skills one must have to come off as a perfect gentleman.

“Men of any worth sit across from women,” he insists, explaining his reasoning for taking up two booths rather than share one with Louis at his favorite diner.

Patti D’Arbanville plays a prostitute who aids Louis in his sexual awakening — lingerie and heterosexual sex. And John C. Reilly is the high-voiced bearded bear of a reclusive, asexual neighbor who sings opera and occasionally fixes Henry’s ancient Electra 225.